There is a constant need within the IVD industry to deliver improvements in performance. Improvements in performance can include accuracy, precision, cost, multiplexing, total test time etc. The novel subtractive corrective assay device and method described in this document is designed to deliver such improvements. The novel subtractive corrective assay device and method is composed of a single use disposable strip and a reusable reader. Although other detection methodologies are applicable, the preferred embodiment focuses on electrochemical detection.
In the prior art there are numerous examples whereby magnetic particles and associated bound species which give detectable changes are brought to a detection zone via a magnetic field. Typically the unbound label is kept away from the detection zone with the bound label being accumulated within the detection zone and inducing the detectable change.
US 2009/0130771 A1 incorporated by reference in its entirety, describes the use of magnetic particles to capture analyte but accumulates them within a detection zone to measure an increased concentration of analyte within the detection zone. US 2009/0130771 A1 also uses a separate reference zone for any background correction. This only works for correction of background of the sample itself and not for any variations in label or other reagent concentrations as the two areas are different and therefore differences will be present with respect to resuspended reagent concentrations as well as the reproducibility of measuring within 2 distinct areas, such as reference vs detection zone size, opacity etc. U.S. 2009/0130771 A1 does make reference to the possibility of using the detection zone for a background measurement but only when “GOD [label] particles are substantially absent from the detection zone” and therefore does not correct for variation in label concentration.
It is amongst the objects of the present invention to provide a cheap and reliable assay system for carrying out IVD tests.
It is amongst the objects of the present invention to provide an assay cartridge design platform and reader which may be easily and cheaply fabricated, as well as being able to be configured to carry out a specified assay or assays.
It is amongst the objects of the present invention to provide an assay cartridge which may easily be adapted to carry out a variety of different specified assays.
It is amongst the objects of the present invention to provide an assay system comprising a reader which may preferably be used or easily adapted to perform a variety of different assays.